Back in the spring, I attended a seminar given at the Institute for Life Course and Aging at the University of Toronto, where the presenter, William McIlroy, Assistant Professor at the Graduate Department of Rehabilitation Science, spoke about age-related changes to our balance and mobility.
The presentation opened with a video showing two different individuals in a lab setting, each standing on a moveable floor, hooked up to electrodes in order to measure the degree of body sway as the platform moved.
In the first experiment, a 25 year-old male stood on the platform. When the floor moved quickly backward, he stepped forward slightly to regain his balance. The same disturbance caused the older subject, a 55 year-old male, to lose his balance entirely. He needed to recover sideways in response to the sudden backward movement. In the next experiment, the platform moved sideways to the left. The 25 year-old made a quick side step in the opposite direction to regain his balance. However, the 55 year-old had to make several corrections in order to steady himself. As the platform moved to the left, his right foot collided with his left and then he had to reach out his hand to the wall in order to regain his balance. The older subject had no physical impairments. He was a healthy, mobile, physically active individual with no history of falls. These videos were used to illustrate some of the changes to balance and mobility which occur as we age.
According to William McIlroy, not all of the systems involved in balance follow the same rate of age-related decline. The sense of touch on the bottom of the feet, which is involved in maintaining an upright posture, decreases faster than the other balance systems. As well there is a slowing down of the “change-in-support” reaction time as we age. This reaction, which allows us to move quickly when there is a disturbance to our centre of support, involves recovery maneuvers such as stepping, reaching. or grasping. In a healthy young adult, there is a rapid onset of this reaction, less than 100 milliseconds (ms). However, in a healthy middle-aged adult, this can slow down to 100-150 ms. This may not seem like much, but it is that slight delay which can cause a fall, if one is not able to quickly step forward, reach, or grasp an object in time.
Researchers at the Centre for Studies in Aging at McGill University have been looking at the effectiveness of interventions such as balance and gait training, lower body strength training, types of footwear, environment and assistive technology, and changes in medication. Here’s what they learned:
- strength training and balance training can’t improve your reaction time, but it will increase your ability to recover from losing your balance, especially laterally (side to side).
- the ability to detect and react to a balance disturbance decreases with age.
- we don’t fully understand where these slow-downs occur in the brain.
- attention and cognitive state are important factors in the risk of falling. Those with Attention Deficit Disorder, Alzheimer’s Disease and dementia are at greater risk of losing their balance but they often avoid situations where they might fall in the first place.
- lateral stability and muscle power will help reduce the risk of falling. (Muscle power is more than just strength — it takes into account the speed at which a muscle can exert force, not just the amount of force it can exert.)
- rapid-strength training (using lower weight at higher speeds) is more beneficial for improving balance and mobility than the more standard strength training which uses higher loads but lower speed.
- people have gotten into the habit of moving slowly during strength and aerobic training (especially treadmill walking and stationary cycling) and this has not allowed them to improve their speed of movement.
- ping-pong is a good exercise because it requires fast action but is low load.
- T’ai Chi is important — not because of speed of motion but because it challenges balance by shifting the centre of support.
- strength training should focus on knee extension, hip flexion, and hip abduction, since these muscles weaken with age.
- proper footwear is key to improving balance and decreasing risk of falls. Specifically:
- avoid heavily-cushioned footwear, which detracts from sensory perception on the foot
- avoid loose-fitting shoes and slippers.
- wear special insoles to increase sensitivity by stimulating the soles of the feet.(Lack of foot sensitivity had a dramatic effect on the ability to balance. In one experiment, participants could not balance after having had their feet placed in ice water.)
Other recommendations included making environmental modifications, both at home and out-of-doors. For example:
- adding handrails
- lighting walking areas so that you can see obstacles in your path
- removing scatter rugs and ensuring that carpet pile is not too thick
- using cueing devices to help visually impaired individuals
The researchers noted that canes can be a hindrance as well as a help. The problem is that they constrain foot movement, so if you fall, the result can be much worse. However, a cane or a walker may be necessary to steady oneself to begin with. Where possible, one should opt for building lower body strength rather than relying on a cane for a crutch!
The researchers also regarded changes in medication as a factor in loss of balance. People who are taking sedatives or antidepressants should talk to their doctor if they are concerned about slowdowns in their reaction time.
McIlroy’s own conclusions were that better clinical tools are needed to assess one’s ability to stabilize and balance, not merely one’s risk of falling. He believed that physical training (balance and strength training) and medication control are the most important things we can do to improve our balance and avoid falls as we age.
What sorts of physical training can we do to improve our balance and avoid falls?
Phillip Page and Michael Rogers, who have published several articles on balance, suggest progressing gradually from less to more difficult exercises, just as you would for any other type of strength training. They suggest starting with simple one-leg stands and other challenges to the base of support, then gradually making the exercises more difficult by adding visual and vestibular challenges (closing the eyes, or looking from side to side). Also, progressing from hard, stable surfaces (such as a floor or thin mat) to a less stable surface (such as a foam pad or wobble board) will improve balance and mobility around the ankle.
Researchers in Australia found that older adults who trained with a wobble board at home saw an improvement in their ability to control the extent of ankle inversion, which is a large predictor of one’s ability to catch oneself when falling.
Rogers and Page recommend that the direction of movement begin in a forward and backward motion and then progress to lateral motion. As with all balance training, one must exercise caution by standing within easy grasp of a stationary object, or work with a qualified balance trainer.
Dean Smith, a physiotherapist who spoke at the 2006 Can-Fit-Pro conference in Toronto this past month, suggests a series of exercises to improve hip, foot and ankle stabilization as well as core (stomach and back) stability and increased upper trunk balance strength. He recommended that personal trainers assess their client’s balance ability through a series of tests, work to improve their balance through physical training, and then retest them. Dean also mentioned the importance of flexibility to ensure good balance. Among other things, Dean uses yoga to improve his clients’ flexibility and strength.
So, although we can expect to see changes that will challenge our balance as we get older, this does not mean that we are destined to experience a debilitating fall. The good news is that so many of these changes can be controlled through a regimen of physical activity and exercise designed to improve balance, mobility, and muscular strength. That, along with a careful check of our environment and ensuring that the effects of medications are being monitored, will reduce our chances of falling.
To your health,
McIlroy, W. (2006). Age related changes to balance and mobility. Institute for Life Course and Aging, March 23. Toronto, ON (unpublished presentation).
Rogers, M. & Page, P. (2003). Making sense of balance. Biomechanics, 0311.
Smith, D. (2006). Balance for healthy knees and feet. Can-Fit-Pro Conference, August 24-27.Toronto, ON (unpublished presentation).
Waddington, G. & Adams, R. The effect of a 5-week wobble-board intervention on ability to discriminate different degrees of ankle inversion, barefoot and wearing shoes: a study in healthy elderly. Journal of the American Geriatrics Society, 52.